Human motion applicator is proposed in Japanese Patent Early Publication No. 2002-48053 which utilizes a memory shape alloy which deforms in response to heat generated by application of electric current for giving a stretching or contracting force to thereby assist a motion intended by a human body. However, due to a limitation to the amount of the displacement and a response speed given to the memory shape alloy, the prior art motion applicator is found insufficient in that it is not completely in match with an actual need of assisting or inducing the human motion.